When I google my website, I only see mydomain.com, but would like to display it as mydomain.com like this image of Facebook's website. How should I do that?

You should specify canonical url.
<link rel="canonical" href="example.com/dresses/green-dresses" />
support.google.com/webmasters/answer/44231 you mean something like this? I am not quite sure if it solves the problem :D it's SEO ... I suck at this ;D
Cool Media Pick
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